new to the site. and the hole audio thing, im more in to supercharging. anyways. now that i got my mustang maxed out for hp atm. i need to hear and feal my music. I own a 03 gt w/ Mach 460 system. i read somewhere that it is a 6ohm so you cant run a 4ohm speaker system in it. which i found out when i bought some alpine to replace my door speakers. my Question is, is there a way to change the amps so i can run a 4 ohm? or should i just get a new cd player and run the speakers off them ( not the subs just speakers). thanks

I doubt they would be 6 ohm in a car, and if its powered by the head unit it should be able to drive 4 ohms. Just measure your stock speakers with a multimeter to see what they are running. Should read about 3.2 ohms DCR (dc resistance).

One more complicated thing you could do ( if the system does indeed have the amp built into the head unit and not a seperate amp in the trunk) , You can take out the head unit, open it up and get the part number off of the chip amp. Google that or post it up here and someone here can help you.

I have had great luck with hacking OEM head units to install preouts or to replace the amp alltogether with a better chipamp.

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they each have their own amp, the front 2 is run off a 1 and the rear is ran off a single one per speaker. i have an article that i will like you too if you would like that explains that it is a 6ohm set up

I would like to see the article because it is very inefficient to run 6 ohm speakers in a car due to power limitations. With 12v and 8 ohms your maximum wattage is about 2 watts. With 12v and 4 ohms your maximum rms wattage is 4.5 watts. When you use a bridge configuration, this theoreticly quadruples because your voltage swing can now go twice your normal operating supply voltage ( typically 13.5v). 13.5*2=27v/2 13.5vrms which is somewhere around 15 watts RMS into 4 ohms. When you use 6 ohms this comes out to aproximatly 9 watts.

This is assuming a chipamp that runs directly on 12v, and not an amp that uses a switching supply to step up the voltage to drive a higher wattage amp. Even with such an amplifier, 6 ohms is not the most efficient. So if your system is indeed 6 ohms, we can try and find out a way to put 4 ohm speakers in it.

HOWEVER! I also found this online:
"I spent the last two weekends replacing the stereo system in my Mustang (most of that time was spent making the custom mounts for the tweeters and the DDX7015 head unit). I'm an acoustician/physicist/electrical engineer by trade and a serious audiophile and let me tell you, the Mach 460 isn't all that it's cracked up to be. Some things I learned:

The door and rear "super sound" speakers (not the tweeters) are rated at 6 ohms. That's been stated before on this board so it should come as no surprise. What killed me was how these drivers were wired. There are two amps that drive these four speakers, each amp driving two speakers in parallel. The parallel wiring drops the impedance seen by the amp to 3 ohms which is why you can't just pop 4-ohm aftermarket drivers in their places since this would make the impedance 2 ohms which is a significant increase in power required of the amp.

Ok, "what's the big deal?" you ask. When I skimmed the circuit schematics I just assumed that each side was wired in parallel, i.e. the left door speaker and left rear speaker are connected to one amp and the right door speaker and right rear speaker connected to the other amp. Nope. While I was trying to figure out a way to use the factory wiring for my new system I saw that the front speakers are wired together and the rear speakers are wired together--you are not getting stereo from the bigger drivers! I don't know how it's wired in the head unit but I'm assuming the two amps are driving the same signal, i.e. mono signal. Unbelievable! :nonono: Don't believe me? Just look at the schematics that you can download from www.flemworld.com"

It seems that the rear woofers are indeed 6 ohms, but run in paralell which puts a 3 ohm load on the amp, which most amps can handle pretty well.

It seems to me a stereo re-wireing is in order ---- that could get pretty messy

However you might be able to get away with running the said speakers in series instead of paralell, this will put an 8 ohm load on the amp instead of 3 ohms, and it will provide half the power, but will allow you to use the new speakers. I would not try 4 ohms in paralell as I do not know the current capabilities of the amplifiers, an amp needs to be able to dish out twice as much current without frying when running into 2 ohms.

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and when necessary use words.

I have read that the headunit is a booger to replace, since there are no wiring harnesses that are designed to adapt to that system. Since the rear speakers are 6 ohm ( are they subs or actual rear speakers with mids/tweeters in them?) and are wired with the front door speakers which are also 6 ohm, this creates a 3 ohm load to each amp. You could easily forgo the wiring to the door speakers ( disconnect them) and run the rear subs as 4 ohms and the amps will be absolutly fine. However that leaves the problem of your door speakers not being powered... I will think on it a bit and see if I Come up with anything, but I think that the best way would unfortunatly be to rewire it..

I own a 1963 falcon with a radio delete, so when I got it wiring was very simple, but I had to fabricate everything myself and keep it hidden to keep the car looking stock. This included everything from running 12 gague wire from my battery to my head unit, the accessory wire from the ignition switch, and running the wires to the rear speakers and sub. I also built a small 15 watt amplifier to power my sub. While wiring in an old car is generally pretty easy, it gets complicated with new cars and could include removing the seats and carpet to properly rewire it, so make sure you have the time to do this if thats what you are planning on.

Do any other members care to comment here?

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always preach the gospel-
and when necessary use words.